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A cup of coffee a day — no more, no less — keeps the doctor away, new research suggests. Photo courtesy of Shutterstock

Research has shown that coffee is good for your heart, and it may protect you against stroke, type 2 diabetes, and cancer. A new study reinforces the benefits of coffee — particularly its cognitive and neuroprotective benefits.

The study, published in the Journal of Alzheimer’s Disease, examined 1,445 people between the ages of 65-84, using data from the Longitudinal Study on Aging (ILSA) in Italy. Interestingly, the researchers found that “cognitively normal” older people who consistently drank more and more coffee over time actually saw higher rates of mild cognitive impairment (MCI) than people who only drank about one cup of coffee a day. People who drank moderate amounts of coffee — about one or two cups a day — had much lower rates of MCI than people who never or rarely drank coffee.

“These findings… suggested that cognitively normal older individuals who never or rarely consumed coffee and those who increased their coffee consumption habits had a higher risk of developing MCI,” the authors write. “Therefore, moderate and regular coffee consumption may have neuroprotective effects… confirming previous studies on the long-term protective effects of coffee, tea, or caffeine consumption and plasma levels of caffeine against cognitive decline and dementia.”

There are several different explanations behind coffee’s neuroprotective features. One mechanism involves the activation of adenosine A2A receptors (A2ARs), which might assist in mitigating damage done by beta-amyloid (the material that forms on the brains of people with Alzheimer’s). In addition, in mice models, researchers have found that moderate caffeine consumption can improve memory, while too much caffeine can give you the jitters and actually impair your memory. And coffee has been linked in the past to reducing the risk of type 2 diabetes, which is a risk factor for cognitive decline.

And lastly, but perhaps most simply, coffee makes you focus and remain attentive, giving your brain an easier time to exercise its mental prowess.

The researchers hope that more in-depth studies will be completed on the subject, in the hopes of pinpointing preventive measures against Alzheimer’s, particularly through diet. “Larger studies with longer follow-up periods should be encouraged, addressing other potential bias and confounding sources, so hopefully opening new ways for diet-related prevention of dementia and AD,” the authors write.